Amazon could build a stake of almost a third in warehouse robotics firm Balyo in the next seven years, as part of a deal that could boost sales of the French company's technology for self-driving forklift trucks.

Warehouse automation is a key element in efforts by Amazon to cut costs and speed up deliveries.

The world's biggest online retailer currently uses robots developed by Kiva Systems, a company it bought for $775 million in 2012.

Amazon could build a stake of almost a third in warehouse robotics firm Balyo in the next seven years as part of the new deal. Pictured, one of the firm's self driving vehicles

'This agreement ... represents an unprecedented opportunity for Balyo to grow its business and supports the soundness of our investments over the years to perfect our robotic solutions,' Balyo Chief Executive Fabien Bardinet said on Thursday.

The firm says its technology enables fleets of robotic trucks to self-locate in real time and navigate inside a building with no added infrastructure, unlike automatic trucks/AGVs.

'Our navigation system, relies on the recognition of the internal fixtures of a building: walls, columns and racks, to enable the trucks to self-locate in real time,' the firm boasts.